Various polyurethanes (PUs) are multibillion dollar commodities and are manufactured worldwide by some of the largest chemical companies (e.g., Dow, DuPont, BASF, and Mitsui). Polyurethanes are used in a wide variety of industrial and clinical applications in the form of, for example, thermoplastics, rubbers, foams, upholstery, tubing, and various biomaterials.
Typically, PUs are made by combining three ingredients: (1) a diol (such as polytetramethylene oxide); (2) a diisocyanate (such as 4,4′-methylene diphenyl diisocyanate); and (3) an extender (such as 1,4-butane diol). Generally, polyurethanes (PUs) contain a soft (rubbery) and a hard (crystalline) component; and the properties of PUs depend on the nature and relative concentration of the soft/hard components.
Even though primary alcohol-terminated PIB compounds, such as HOCH2-PIB-CH2OH, have been prepared in the past previous synthesis methods have been uneconomical. As such, the cost of manufacturing primary alcohol-terminated PIB compounds has been too high for commercial production. One reason for the high cost associated with manufacturing primary alcohol-terminated PIB compounds, such as HOCH2-PIB-CH2OH, is that the introduction of a terminal —CH2OH group at the end of the PIB molecule necessitates the use of the hydroboration/oxidation method—a method that requires the use of expensive boron chemicals (H6B2 and its complexes).
Given the above, numerous efforts have been made to develop an economical process for manufacturing primary alcohol-terminated PIB compounds, such as HOCH2-PIB-CH2OH. For example, BASF has spent millions of dollars on the research and development of a process to make HOCH2-PIB-CH2OH by hydroboration/oxidation, where such a process permitted the recovery and reuse of the expensive boron containing compounds used therein. Other research efforts have been made, and have met with limited success in reducing the cost associated with producing primary alcohol-terminated PIB compounds, such as PIB-CH2OH or HOCH2-PIB-CH2OH.
With regard to amine-terminated PIBs, early efforts directed toward the synthesis of amine-terminated telechelic PIBs were both cumbersome and expensive, and the final structures of the amine-telechelic PIBs are different from those described below.
More recently, Binder et al. (see, e.g., D. Machl, M. J. Kunz and W. H. Binder, Polymer Preprints, 2003, 44(2), p. 85) initiated the living polymerization of isobutylene under well-known conditions, terminated the polymer with 1-(3-bromopropyl)-4-(1-phenylvinyl)-benzene, and effected a complicated series of reactions on the product to obtain amine-terminated PIBs. Complex structures very different from those disclosed herein were obtained and the above method did not yield amine-terminated telechelic PIB compounds.
Given the above, there is a need in the art for a manufacturing process that permits the efficient and cost-effective production/manufacture of primary alcohol-terminated PIB compounds, primary amine-terminated PIB compounds, primary methacrylate-terminated PIB compounds, and/or primary amine-terminated telechelic PIB compounds.